Plant Disease (2020) 104, 3143-3150

You Li, James Skelton, Sawyer Adams, Yukako Hattori, Matthew E. Smith and Jiri Hulcr (2020)
The ambrosia beetle Sueus niisimai (Scolytinae: Hyorrhynchini) is associated with the canker disease fungus Diatrypella japonica (Xylariales)
Plant Disease 104 (12), 3143-3150
Abstract: Ambrosia beetles in the subtribe Hyorrhynchini are one example of an entire ambrosia beetle lineage whose fungi have never been studied. Here, we identify one dominant fungus associated with a widespread Asian hyorrhynchine beetle Sueus niisimai. This fungus was consistently isolated from beetle galleries from multiple collections. Phylogenetic analyses of combined ITS rDNA and β-tubulin sequences identified the primary fungal symbiont as Diatrypella japonica Higuchi, Nikaido and Hattori (Diatrypaceae, Xylariales, Sordariomycetes), which was recently described as a pathogen of sycamore (Platanus spp.) in Japan. To assess the invasion potential of this beetle-fungus interaction into the U.S., we have investigated the pathogenicity of two D. japonica strains on four species of healthy landscape trees native to the southeastern United States. Only Shumard oak (Quercus shumardii) responded with lesions significantly greater than the control inoculations, but there was no observable dieback or tree mortality. Although disease symptoms were not as prominent as in previous studies of the same fungus in Japan, routine reisolation from the inoculation point suggests that this species is capable of colonizing healthy sapwood of several tree species. Our study shows that the geographical area of its distribution is broader in Asia and potentially includes many hosts of its polyphagous vector. We conclude that the Sueus-Diatrypella symbiosis has high invasion potential but low damage potential, at least on young trees during the growing season.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Jiri Hulcr

Research topic(s) for pests/diseases/weeds:
transmission/dispersal of plant diseases

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Sueus niisimai	Oak (Quercus)	Japan
	Diatrypella japonica	Oak (Quercus)	Japan
	Diatrypella japonica	Plane tree/sycamore (Platanus)	Japan